Zacapa Resources Ltd. (TSXV: ZACA, DE: BH0) is pleased to announce that the first four holes (RT-21-001 and RT-22-002 through RT-22-004) have cut porphyry style alteration and veining with multiple intervals containing visible copper minerals and further expanding the volume of hydrothermal alteration at Red Top to vertical depths of more than 800 metres. A fifth drill hole is underway with a planned depth of 1,200 metres to explore deeper portions of the 100% owned Red Top porphyry copper project in the Superior Mining District, Arizona.
Drill holes RT-21-001, RT-22-002, RT-22-003 and RT-22-004 were designed to test the copper potential at depth beneath a >3.5 kilometre by 1.5 kilometre outcropping quartz-sericite-pyrite alteration zone with a core of advanced argillic alteration (pyrophyllite-illite-sericite) (Figure 1). Similar to the previously released drill holes (RT-21-001, RT-22-002, and RT-22-003), RT-22-004 cut a series of texturally distinct hypabyssal quartz feldspar porphyry intrusions and importantly diabase intrusions with varying intensities of porphyry related hydrothermal alteration (quartz-sericite-pyrite and possibly sericite-chlorite after biotite), porphyry style “A-Veins”, porphyry style “B-Veins” and intermittent intervals containing chalcopyrite and bornite mineralization commonly associated with what appear to be late-stage, open space quartz veins (Figure 2).
Highlights:
- Porphyry style alteration, veining and mineralization has been confirmed with diamond drilling over an area measuring 1,200 meters by 800 meters and over a vertical extent of over 800 meters increasing Zacapa’s confidence that a significant hydrothermal system is present and has the potential to host significant copper mineralization.
- In addition to the large volume of alteration, numerous favourable host rock lithologies are present including at least three phases of texturally distinct hypabyssal quartz-feldspar (+/- hornblende) porphyry intrusions and importantly iron-rich diabase intrusions which are a key high grade host rock at the nearby (8 kilometers) Rio Tinto/BHP Resolution mine development project (1.8 Bt @ 1.5% Cu)2,4.
- Zacapa is leveraging recently collected airborne (MobileMT) and magnetic geophysical survey to help vector toward a potentially higher temperature, more intensely altered copper-rich core to this newly identified porphyry system in the prolific Superior Mining District of Arizona.
- Drill hole number five (RT-22-005) is a near vertical hole situated between drill holes RT-21-001 and RT-22-003 and is currently at 604 metres depth.
“We are very pleased by the ongoing drill success at Red Top and the further expansion of a new porphyry footprint in one of the world’s top porphyry copper districts. The geological context and geometry of the target area are coming into focus and we look forward to establishing Red Top as a premier copper exploration project,” comments Adam Melnik, Chief Executive Officer. “Zacapa is incorporating the newly acquired geophysical data along with more detailed mapping and remote sensing to assist us in vectoring toward the core of a new copper-molybdenum porphyry system in Arizona.”
Figure 1 – Red Top geologic map and location of the 2022 diamond drill holes.
Figure 2 – Selection of alteration and host rock examples from Red Top Drilling to date.; A) Quartz “A-Vein”(red arrow) cut by QSP vein (blue arrow) B) Strong flooding/corridors (green arrow) and veins/veinlets of QSP cutting granite porphyry C) Porphyry “B-Vein” (yellow arrow) D) Intense chlorite altered diabase intrusion (reactive host rocks influence higher grade copper at nearby Resolution Deposit2,4 E) Quartz-Chlorite-Sericite vein with bleached selvage with chalcopyrite rimmed by bornite (orange arrow). Diamond drill holes RT-21-001 through RT-22-004 contain pervasive alteration of varying intensity and intermittent copper, gold, and base metal mineralization in favourable host rocks including multiphase porphyritic intrusions, schist, and diabase intrusions confirmed by diamond drilling over an area measuring 1,200 by 800 meters and to a depth of more than 800 meters from surface. Alteration mineral assemblages including quartz-sericite-pyrite and chlorite-sericite (after biotite) in diamond drilling and pyrophyllite-illite-sericite exposed at surface together with mineralization including vein-controlled chalcopyrite, galena, and sphalerite suggest the first four holes have tested geology either above or lateral to a copper bearing “core” in an idealized porphyry system (Figure 4). Surface mapping and historical Induced Polarization geophysics suggest that the Red Top system is tilted moderately toward the east suggesting that the system plunges moderately toward the west (see Figure 4). Ongoing exploration targeting at Red Top will leverage new geological information collected in the first four drill holes as well as newly acquired magnetic and electromagnetic data from the recently completed MobileMT survey to vector toward a potential copper-rich core to this system which may be located lateral to the west of the current drill holes or deeper in the system (Figure 4).
Figure 3 – Surface geology (3A) compared to 2-D geophysical features derived from Zacapa’s MobileMT airborne survey has identified a coincident total magnetic intensity magnetic transitional feature (3B), a conductivity feature (3C) and resistivity feature (3D) which together represent a high priority anomaly and potential drill target.
Drill Hole Descriptions
Drill Hole RT-22-003
Drill hole RT-22-003 was collared 360 metres north of RT-21-001 and drilled to a total depth of 986 meters (Table 1). The hole was drilled to expand Zacapa’s understanding of alteration and mineral zonation within the newly identified hydrothermal system and assist in vectoring toward the associated porphyry center. RT-22-003 cut a series of granitic porphyry intrusions with variable phenocryst abundances and sizes hosted by a quartz-monzonite micro-porphyry. The granite porphyry is characterized by a weak but pervasive sericite+/-chlorite alteration mineral assemblage. Sericite and chlorite are present as vein halos, ranging from 0.1-3 cm in width, and are common throughout the drillhole cutting all porphyry rocks. Below 811 metres, much of the quartz-monzonite and other porphyritic intrusions contain patchy to pervasive albitization of feldspar phenocryst. Sulphide mineralization in RT-22-003 includes vein hosted pyrite ± chalcopyrite ± bornite ± sphalerite ± galena, fracture filling pyrite, and disseminated magnetite ± pyrite. Except for magnetite, mineralization is spatially associated with veins and intervals of increased vein density.
Drill Hole RT-22-004
Diamond drillhole RT-22-004 (Table 1) was collared 650 metres north of RT-22-003 and oriented to test an Induced Polarization chargeability geophysical anomaly by drilling to the west-northwest from an area of high to low chargeability. RT-22-004 intersected a thin interval of Pinal Schist cut by a coarse-grained granodiorite porphyry at 24 metres depth. Below 24 metres the hole intersected alternating layers of dark, fine- to medium-grained diabase and granodiorite. From 437 to 623 metres (EOH), the dominant lithology is a pink to greyish-pink granite porphyry. Intense alteration/mineralization was present within the Pinal schist and granodiorite porphyry from 11-150 metres including locally over 20 percent pyrite. The alternating sequence of diabase-granodiorite are present to 437 metres depth and contain weak chlorite and sericite alteration. Sericite altered plagioclase phenocrysts and magnetite-chlorite altered biotite is common through much of the granite porphyry intersected in latter portion of the drillhole. Chlorite-sericite alteration is also present as vein halos and sericite increases to a pervasive overprint of the porphyry groundmass where veining is most abundant. Sulphide mineralization in RT-22-004 comprises vein hosted pyrite ± chalcopyrite ± bornite ± sphalerite ± galena and disseminated magnetite ± pyrite. Magnetite is present in all lithologies and tends to occur as small veinlets and as disseminations.
Table 1 – Red Top drill hole collar information
Airborne MobileMT Geophysics
Geophysical Interpretation and Targeting
Expert Geophysics Limited (“EGL”) conducted a helicopter-borne MobileMT electromagnetic and magnetic survey over Red Top in late February 2022. The objective of the survey was to collect apparent magnetic, conductivity and resistivity data to aid in the three-dimensional targeting and geological modeling of the Red Top porphyry center in the subsurface (Figure 2). Systematic modeling of these data are ongoing however, interpretation of 2-dimensional products has highlighted a total magnetic intensity, apparent conductivity and resistivity features of interest including a coincident magnetic low to high transition interpreted to represent magnetite destruction (Figure 2B), a resistivity low reflecting alteration or a buried intrusion (Figure 2D) and an apparent conductivity high which may represent the presence of sulphide minerals associated with alteration or mineralization (Figure 2C). These geophysical features together are considered a high priority anomaly and potential new drill target.
Survey Parameters
The MobileMT electromagnetic and magnetic survey at Red Top consisted of four production flights covering 199 line-kilometers of survey data over a 73 sq km area. The survey lines were oriented E-W (90°N) at 400 metre spacing, with tie lines oriented perpendicular to the survey lines and spaced at 4,000 metres.
Figure 4 – Simplified, idealized and westward tilted porphyry copper alteration and metal zonation cross sectional model showing the schematic location of holes RT-21-001 through RT-22-004 modified from Lowell and Guilbert 19705.
About the Red Top Porphyry Copper Project
The Red Top porphyry copper project is located in the Superior Mining District, 8 kilometres northwest of the Rio Tinto and BHP’s Resolution mine development project and approximately 11 kilometres from the Carlota and Pinto Valley mining operations. Red Top is comprised of 431 unpatented mining claims covering 8,377 acres. The Red Top project area exhibits widespread porphyry style alteration with locally intense alteration spanning approximately 3.5 kilometres by 1.5 kilometres near Red Top hill. These intensely altered areas of quartz-sericite, as well as zones of pyrophyllite and illite are analogous to assemblages associated with mineralization at the upper levels of the Resolution deposit2,3. This alteration and mineralization at Red Top are interpreted as the expression of the upper levels of a now moderately tilted porphyry system that has only seen limited historical exploration and no previous drilling within the target area. Zacapa is one of the only exploration companies drilling for porphyry copper in southeast Arizona, which is dominated by Freeport, BHP and Rio Tinto.
About Zacapa Resources
Zacapa is a copper and gold focused mineral exploration company engaged in responsible exploration for the new energy economy. Its projects are concentrated in world class jurisdictions in the southwest U.S., including Arizona, Nevada, and Idaho. The portfolio includes porphyry copper projects at Red Top, Pearl, and Dewdrop Moon, and epithermal gold projects at South Bullfrog and Miller Mountain. These assets are being advanced by a highly disciplined and seasoned professional team with successful track records of discovery, resource development and mine permitting.
References
1 Alteration and sulphide mineralogy has been determined visually from drill core and confirmed where possible using Portable XRF (“pXRF”) and short-wave infrared (SWIR) analytical devices. Petrographic samples have been collected and will be used expand upon visual observations.
2 References to other mines and deposits made in this news release provide context for the Red Top Project, which occurs in a similar geologic setting, but this is not necessarily indicative that Red Top hosts similar grades and tonnages of mineralization.
3 Manske, S.L., and Paul, A.H., 2002, Geology of a major new porphyry copper center in the Superior (Pioneer) district, Arizona: Economic Geology, v. 97, no. 2, p. 197-220.
4 Rio Tinto, 2020, Annual Report
5 Lowell, J.D. and Guilbert, J.M. (1970) Lateral and Vertical Alteration-Mineralization Zoning in Porphyry Ore Deposits. Economic Geology, 65, 373-408.
Qualified Person Daniel MacNeil, P.Geo, a Qualified Person as defined by National Instrument 43-101, has read and approved all technical and scientific information related to Red Top contained in this news release. Mr. MacNeil is at Technical Advisor to Zacapa Resources and has verified the data disclosed in this press release, including the sampling, analytical and test data underlying the information.